Abstract:
:Although fully explored in larger animals, the role of injection site and sample microsphere content on variability of coronary blood flow (CBF) measurement using the microsphere technique remains controversial in rats despite the fact that this species is extensively used in cardiovascular research. We therefore investigated these variables in two studies. In a first study, we established that the precision of the method, assessed by the variability of four simultaneous CBF determinations, was a function of the sample microsphere number. Coefficient of variation (CV) averaged 4-10% when the tissue and reference samples received greater than 1000 and greater than 100 spheres, respectively, and did not improve appreciably with larger numbers of microspheres. In a second study, flow CV was measured following left atrial (LA) or left ventricular (LV) microsphere injections performed nearly simultaneously in the same conscious animal or in two similar groups of animals. CBF variability was lower by 22-62% after LA than after LV injections. Estimates obtained from separate analysis of the main variability components indicated that, with one exception, the variability associated with LV injections was at least 1.4 to 2.8 times higher than that due to LA injections. These findings establish the minimum number of microspheres needed to obtain precise blood flow determinations in the rat model and confirm previous reports, in anaesthetised rats, that LA microsphere injections generally yield more precise coronary blood flow determinations than LV injections.
journal_name
Cardiovasc Resjournal_title
Cardiovascular researchauthors
Wicker PA,Healy BPdoi
10.1093/cvr/23.5.443subject
Has Abstractpub_date
1989-05-01 00:00:00pages
443-52issue
5eissn
0008-6363issn
1755-3245journal_volume
23pub_type
杂志文章abstract:AIMS:Despite their ability to cause septic shock and myocardial dysfunction, components of Gram-negative bacterial cell walls, like lipopolysaccharide, have been shown in numerous studies to induce myocardial protection during ischaemia-reperfusion injury. Muramyl dipeptide (MDP) is another such component recognized by...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvp055
更新日期:2009-07-15 00:00:00
abstract::Many observational studies and experimental and animal studies have demonstrated that estrogen therapy (ET) or hormone therapy (HT) significantly reduces the risk of coronary heart disease. Nonetheless, recent randomized controlled trials and the Nurses' Health Study in secondary prevention demonstrate trends toward a...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1016/j.cardiores.2005.12.004
更新日期:2006-04-01 00:00:00
abstract::Supravalvar aortic banding was performed in 6 to 12 week puppies. Sixteen animals were studied 7.3 (3.5 to 10) months later, closed-chested under morphine-chloralose, catheters being positioned in the great vessels and heart, including the left atrium for microsphere injection. Compared with 11 controls, eight dogs de...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/15.12.711
更新日期:1981-12-01 00:00:00
abstract:OBJECTIVE:Anisotropic conduction characteristics, which may be expressed as the ratio of conduction velocities in the longitudinal (Vlong) and transverse (Vtrans) fibre directions, have been shown to stabilise reentry and favour the induction of sustained, uniform ventricular tachycardia. The aim of this study was to i...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(96)88593-2
更新日期:1995-03-01 00:00:00
abstract:STUDY OBJECTIVE:The aim was to investigate the effects of long-term treatment with an alpha 1 blocker, bunazosin hydrochloride, on blood pressure, heart weight, myocardial contractility, and ventricular myosin isoenzyme pattern in spontaneously hypertensive rats (SHR). DESIGN:Bunazosin hydrochloride was given orally i...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/25.7.565
更新日期:1991-07-01 00:00:00
abstract::Most of our knowledge about the modulation of platelet function by catecholamines is based on observations of acute in vitro actions. Little is known about the effects of chronically elevated or reduced adrenergic stimulation of the platelets. We therefore treated rats for 8 weeks with either adrenaline or the beta-bl...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/23.2.112
更新日期:1989-02-01 00:00:00
abstract:AIMS:Autonomic dysfunction can promote atrial fibrillation (AF) and results from AF-related remodelling. N-type Ca2+-channels (NTCCs) at sympathetic nerve terminals mediate Ca2+-entry that triggers neurotransmitter release. AF-associated remodelling plays an important role in AF pathophysiology but the effects of NTCC ...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvz136
更新日期:2019-12-01 00:00:00
abstract:OBJECTIVE:Myocardial contractility is enhanced in transgenic (TG) mice with cardiac-restricted overexpression of the alpha1A-adrenergic receptors (alpha1A-AR). We tested the hypothesis that this enhanced inotropy protects against dysfunction and remodeling after myocardial infarction (MI). METHODS:We subjected alpha1A...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/j.cardiores.2006.06.015
更新日期:2006-09-01 00:00:00
abstract::The contractile response to beta-adrenoceptor stimulation has been found to be reduced in single myocytes from failing human ventricle. A portion of that reduction was statistically related to the age of the patient. We have developed a method for obtaining viable contracting myocytes from small biopsies of human vent...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:
更新日期:1996-01-01 00:00:00
abstract:STUDY OBJECTIVE:It has been suggested that oxygenation of the isolated, crystalloid perfused, Langendorff rabbit heart is inadequate and that consequent hypoxia limits mechanical performance. The isolated working rabbit heart, which has a higher oxygen requirement than the Langendorff preparation, was used to investiga...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/25.3.198
更新日期:1991-03-01 00:00:00
abstract:AIMS:Antihypertensive drugs are included in the medical therapy of vascular Ehlers-Danlos syndrome (vEDS). The β-blocker celiprolol has been suggested to prevent arterial damage in vEDS, but the underlying mechanism remains unclear. It is also unknown whether the widely used angiotensin II receptor type 1 antagonist lo...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvz095
更新日期:2020-02-01 00:00:00
abstract:STUDY OBJECTIVE:The aim was to compare the temporal sequence and structural relationship between perivascular and interstitial fibrosis and microscopic scarring seen in the left ventricle in response to either a transient or sustained stimulus to fibrosis. DESIGN:In 72 male Wistar rats (250-350 g) the transient stimul...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/24.9.741
更新日期:1990-09-01 00:00:00
abstract:UNLABELLED:Recent investigations have established the feasibility of using exogenously delivered angiogenic growth factors to increase collateral artery development in animal models of myocardial and hindlimb ischemia. OBJECTIVE:Our aim was to evaluate the ability of a stabilized form of acidic fibroblast growth facto...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(03)00522-4
更新日期:2003-10-01 00:00:00
abstract:OBJECTIVE:The aim was to test the hypothesis that nitric oxide (or a related compound) contributes to the coronary vasodilatation during physiological increases of myocardial O2 consumption that occur with exercise. METHODS:Active hyperaemia associated with graded treadmill exercise and coronary reactive hyperaemia we...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/28.1.119
更新日期:1994-01-01 00:00:00
abstract:AIMS:Vascular endothelial growth factor-C (VEGF-C) has been shown to stimulate both angiogenesis and lymphangiogenesis in some but not all models where VEGF-C is over-expressed. Our aim was to investigate the interaction between lymphangiogenesis and angiogenesis in adult tissues regulated by VEGF-C and identify eviden...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvm094
更新日期:2008-05-01 00:00:00
abstract:OBJECTIVE:The presence is well established in unstable angina of intracoronary thrombosis in a stenosed epicardial coronary artery. The effects of the thrombus formation on the distal microcirculation are however still unclear. METHODS:We adapted the Folts canine model of left circumflex coronary arterial stenosis and...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(98)00270-3
更新日期:1999-04-01 00:00:00
abstract::Because of ventricular interdependence, part of the measured left ventricular diastolic pressure can be attributed to the right ventricle. Therefore, we examined the hypothesis that left ventricular diastolic properties are modified by alterations in right ventricular compliance and pressure even without a change in r...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/22.11.768
更新日期:1988-11-01 00:00:00
abstract:BACKGROUND:Plasma low density lipoproteins (LDL) play a key role in the pathogenesis of atherosclerosis. LDL modify gene expression in vascular cells leading to disturbances in the functional state of the vessel wall. METHODS:Expression levels of C-4 sterol methyl oxidase gene (ERG25), sterol regulatory element bindin...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(02)00856-8
更新日期:2003-04-01 00:00:00
abstract:OBJECTIVE:The objective of this study was to investigate the relationship between acute decreases in right ventricular volume during Valsalva strain (with resultant changes in autonomic neural tone) and measures of local endocardial repolarization time independent of heart rate and autonomic neural tone. METHODS:Patie...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(99)00261-8
更新日期:2000-01-14 00:00:00
abstract::Congenital coronary artery anomalies are of major significance in clinical cardiology and cardiac surgery due to their association with myocardial ischaemia and sudden death. Such anomalies are detectable by imaging modalities and, according to various definitions, their prevalence ranges from 0.21 to 5.79%. This cons...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1093/cvr/cvv251
更新日期:2016-02-01 00:00:00
abstract:BACKGROUND:The mechanism of defibrillation is controversial. Reentry appearing immediately after the shock has been shown to be responsible for defibrillation failure in some studies while other studies have demonstrated that a rapid train of focal activations with the first focus appearing >50 ms after the shock is re...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/j.cardiores.2003.10.009
更新日期:2004-01-01 00:00:00
abstract:OBJECTIVES:To investigate the effect of alpha,beta(1) and beta(2) adrenergic receptor (AR) stimulation on coronary hemodynamics, myocardial oxygen consumption (M(v)O(2)) and metabolic substrate preference in advanced dilated cardiomyopathy (DCM). METHODS:We studied 19 conscious, instrumented dogs with pacing-induced D...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1016/s0008-6363(01)00490-4
更新日期:2002-02-01 00:00:00
abstract:OBJECTIVE:The Na+ activated K+ channel (IK(Na)) may be activated during ischaemia when the intracellular Na+ concentration is raised. As ischaemia is also associated with intracellular acidification, the influence of intracellular pH on this K+ channel was investigated. METHODS:The effects of intracellular Na+ and H+ ...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/28.7.1036
更新日期:1994-07-01 00:00:00
abstract::The cardioprotective effects of mioflazine, a recently developed cardiovascular drug, were investigated in 41 anaesthetised open chest Beagle dogs subjected to 1 h normothermic global myocardial ischaemia. The severity of the model is evidenced by the finding that only one out of 20 control dogs could be weaned from e...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/18.9.528
更新日期:1984-09-01 00:00:00
abstract::Ischemic preconditioning is a powerful biologic phenomenon that activates innate cell survival programs to protect the heart from ischemic injury. The preponderance of research into classical ischemic preconditioning has focused on signaling pathways orchestrating cardioprotection. Conceptually classified into trigger...
journal_title:Cardiovascular research
pub_type: 杂志文章,评审
doi:10.1016/s0008-6363(03)00337-7
更新日期:2003-07-01 00:00:00
abstract:AIMS:Atrial fibrillation (AF) is a progressive cardiac arrhythmia that increases the risk of hospitalization and adverse cardiovascular events. There is a clear demand for more inclusive and large-scale approaches to understand the molecular drivers responsible for AF, as well as the fundamental mechanisms governing th...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvaa307
更新日期:2020-10-29 00:00:00
abstract::STUDY OBJECTIVE - The aim of the study was to determine the changes in the beta adrenergic system induced by cardiac hypertrophy due to valvular aortic stenosis. DESIGN - Density of beta adrenoceptors, cardiac tissue noradrenalime concentrations, coronary blood flow (using radioactive microspheres), and haemodynamic v...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/24.1.65
更新日期:1990-01-01 00:00:00
abstract:AIMS:Chronic heart failure is a complex clinical syndrome with impaired myocardial contractility. In failing cardiomyocytes, decreased signalling efficiency between the L-type Ca(2+) channels (LCCs) in the plasma membrane (including transverse tubules, TTs) and the ryanodine receptors (RyRs) in the sarcoplasmic reticul...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvt030
更新日期:2013-05-01 00:00:00
abstract::STUDY OBJECTIVE - The aim of the study was to reassess the role of reactive oxygen species in causing reperfusion arrhythmias, which they might do either by directly generating free oxygen radicals or by using scavengers of free oxygen radicals. DESIGN - Ventricular arrhythmias were studied in isolated rat hearts (n =...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/24.2.156
更新日期:1990-02-01 00:00:00
abstract:AIMS:Elderly patients with heart failure with reduced ejection fraction (HFrEF) have worse prognosis and less often receive guideline-recommended therapies. We aim to better understand the underlying pathophysiological processes associated with aging in HFrEF potentially leading to targeted therapies in this vulnerable...
journal_title:Cardiovascular research
pub_type: 杂志文章
doi:10.1093/cvr/cvaa279
更新日期:2020-10-01 00:00:00